In                    package:ggm                    R Documentation

_I_n_d_i_c_a_t_o_r _m_a_t_r_i_x

_D_e_s_c_r_i_p_t_i_o_n:

     Finds the indicator matrix of the zeros of a matrix.

_U_s_a_g_e:

     In(A)

_A_r_g_u_m_e_n_t_s:

       A: a matrix.

_D_e_t_a_i_l_s:

     The indicator matrix is a matrix of zeros and ones which has a
     zero element iff the corresponding element of 'A' is (exactly)
     zero.

_V_a_l_u_e:

     a matrix of the same dimensions as 'A'.

_A_u_t_h_o_r(_s):

     Giovanni M. Marchetti

_R_e_f_e_r_e_n_c_e_s:

     Wermuth, N. & Cox, D.R. (2003). Joint response graphs and
     separation induced by triangular systems. Submitted and available
     at <URL: http://psystat.sowi.uni-mainz.de>.

_S_e_e _A_l_s_o:

     'DAG', 'inducedCovGraph', 'inducedConGraph'

_E_x_a_m_p_l_e_s:

     ## A simple way to find the overall induced coincentration graph
     ## The DAG on p. 198 of Cox & Wermuth (1996)
     amat <- DAG(y1 ~ y2 + y3, y3 ~ y5, y4 ~ y5)
     A <- edgeMatrix(amat)
     In(crossprod(A))

